From c9374115112a6fc0d1dfb36663cff1d5933f1fef Mon Sep 17 00:00:00 2001 From: "David E. O'Brien" Date: Thu, 27 Sep 2001 20:50:14 +0000 Subject: RFC2349 (http://www.hypermail.org/rfcs/rfc2349.html) adds support for negotiation of timeout and file size to the tftp protocol. This is required by some firmware like EFI boot managers (at least on HP i2000 Itanium servers) in order to boot an image using tftp. The attached patch implements the RFC, and in doing so also implements RFC2347; a generic tftp option extension. PR: 30710 Submitted by: Espen Skoglund --- libexec/tftpd/tftpd.c | 129 ++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 120 insertions(+), 9 deletions(-) (limited to 'libexec') diff --git a/libexec/tftpd/tftpd.c b/libexec/tftpd/tftpd.c index f219f081bf42..8740fd129e79 100644 --- a/libexec/tftpd/tftpd.c +++ b/libexec/tftpd/tftpd.c @@ -79,10 +79,11 @@ static const char rcsid[] = #include "tftpsubs.h" #define TIMEOUT 5 +#define MAX_TIMEOUTS 5 int peer; int rexmtval = TIMEOUT; -int maxtimeout = 5*TIMEOUT; +int max_rexmtval = 2*TIMEOUT; #define PKTSIZE SEGSIZE+4 char buf[PKTSIZE]; @@ -110,6 +111,7 @@ static int ipchroot; static char *errtomsg __P((int)); static void nak __P((int)); +static void oack __P(()); int main(argc, argv) @@ -311,6 +313,21 @@ struct formats { { 0 } }; +struct options { + char *o_type; + char *o_request; + int o_reply; /* turn into union if need be */ +} options[] = { + { "tsize" }, /* OPT_TSIZE */ + { "timeout" }, /* OPT_TIMEOUT */ + { NULL } +}; + +enum opt_enum { + OPT_TSIZE = 0, + OPT_TIMEOUT, +}; + /* * Handle initial connection protocol. */ @@ -320,9 +337,9 @@ tftp(tp, size) int size; { register char *cp; - int first = 1, ecode; + int i, first = 1, has_options = 0, ecode; register struct formats *pf; - char *filename, *mode; + char *filename, *mode, *option, *ccp; filename = cp = tp->th_stuff; again: @@ -350,7 +367,40 @@ again: nak(EBADOP); exit(1); } + while (++cp < buf + size) { + for (i = 2, ccp = cp; i > 0; ccp++) { + if (ccp >= buf + size) { + nak(EBADOP); + exit(1); + } else if (*ccp == '\0') + i--; + } + for (option = cp; *cp; cp++) + if (isupper(*cp)) + *cp = tolower(*cp); + for (i = 0; options[i].o_type != NULL; i++) + if (strcmp(option, options[i].o_type) == 0) { + options[i].o_request = ++cp; + has_options = 1; + } + cp = ccp-1; + } + + if (options[OPT_TIMEOUT].o_request) { + int to = atoi(options[OPT_TIMEOUT].o_request); + if (to < 1 || to > 255) { + nak(EBADOP); + exit(1); + } + else if (to <= max_rexmtval) + options[OPT_TIMEOUT].o_reply = rexmtval = to; + else + options[OPT_TIMEOUT].o_request = NULL; + } + ecode = (*pf->f_validate)(&filename, tp->th_opcode); + if (has_options) + oack(); if (logging) { char host[MAXHOSTNAMELEN]; @@ -468,6 +518,14 @@ validate_access(filep, mode) return (err); *filep = filename = pathname; } + if (options[OPT_TSIZE].o_request) { + if (mode == RRQ) + options[OPT_TSIZE].o_reply = stbuf.st_size; + else + /* XXX Allows writes of all sizes. */ + options[OPT_TSIZE].o_reply = + atoi(options[OPT_TSIZE].o_request); + } fd = open(filename, mode == RRQ ? O_RDONLY : O_WRONLY|O_TRUNC); if (fd < 0) return (errno + 100); @@ -478,15 +536,13 @@ validate_access(filep, mode) return (0); } -int timeout; +int timeouts; jmp_buf timeoutbuf; void timer() { - - timeout += rexmtval; - if (timeout >= maxtimeout) + if (++timeouts > MAX_TIMEOUTS) exit(1); longjmp(timeoutbuf, 1); } @@ -515,7 +571,7 @@ xmitfile(pf) } dp->th_opcode = htons((u_short)DATA); dp->th_block = htons((u_short)block); - timeout = 0; + timeouts = 0; (void)setjmp(timeoutbuf); send_data: @@ -578,7 +634,7 @@ recvfile(pf) ap = (struct tftphdr *)ackbuf; block = 0; do { - timeout = 0; + timeouts = 0; ap->th_opcode = htons((u_short)ACK); ap->th_block = htons((u_short)block); block++; @@ -651,6 +707,7 @@ struct errmsg { { EBADID, "Unknown transfer ID" }, { EEXISTS, "File already exists" }, { ENOUSER, "No such user" }, + { EOPTNEG, "Option negotiation" }, { -1, 0 } }; @@ -700,3 +757,57 @@ nak(error) if (send(peer, buf, length, 0) != length) syslog(LOG_ERR, "nak: %m"); } + +/* + * Send an oack packet (option acknowledgement). + */ +static void +oack() +{ + struct tftphdr *tp, *ap; + int size, i, n; + char *bp; + + tp = (struct tftphdr *)buf; + bp = buf + 2; + size = sizeof(buf) - 2; + tp->th_opcode = htons((u_short)OACK); + for (i = 0; options[i].o_type != NULL; i++) { + if (options[i].o_request) { + n = snprintf(bp, size, "%s%c%d", options[i].o_type, + 0, options[i].o_reply); + bp += n+1; + size -= n+1; + if (size < 0) { + syslog(LOG_ERR, "oack: buffer overflow"); + exit(1); + } + } + } + size = bp - buf; + ap = (struct tftphdr *)ackbuf; + signal(SIGALRM, timer); + timeouts = 0; + + (void)setjmp(timeoutbuf); + if (send(peer, buf, size, 0) != size) { + syslog(LOG_INFO, "oack: %m"); + exit(1); + } + + for (;;) { + alarm(rexmtval); + n = recv(peer, ackbuf, sizeof (ackbuf), 0); + alarm(0); + if (n < 0) { + syslog(LOG_ERR, "recv: %m"); + exit(1); + } + ap->th_opcode = ntohs((u_short)ap->th_opcode); + ap->th_block = ntohs((u_short)ap->th_block); + if (ap->th_opcode == ERROR) + exit(1); + if (ap->th_opcode == ACK && ap->th_block == 0) + break; + } +} -- cgit v1.3